1. Institute of Nanoscience and Materials of Aragon (INMA), Spanish Research Council-University of Zaragoza (CSIC-University of Zaragoza), Zaragoza, Spain
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Dr. Jose L. Hueso
1. Institute of Nanoscience and Materials of Aragon (INMA), Spanish Research Council-University of Zaragoza (CSIC-University of Zaragoza), Zaragoza, Spain
Cesium lead halide perovskite nanocrystals are being lately explored for optoelectronic applications due to their emission tunability, high photoluminescence quantum yields, and narrow emission bands. Nevertheless, their incompatibility with polar solvents and composition homogenization driven by a fast anion-exchange are still important drawbacks to overcome. Herein we report on a successful encapsulation of colloidal perovskite nanocrystals within solid–lipid structures mainly consisting of stearic acid. The product is water-stable for a period longer than 2 months and anion-exchange is fully arrested when mixing nanocrystals of different halide compositions. This strategy boosts the potential applications of all-inorganic perovskite nanocrystals for ink-printing.
Research in solid-gas heterogeneous catalytic processes is typically aimed toward optimization of catalyst composition to achieve a higher conversion and, especially, a higher selectivity. However, even with the most selective catalysts, an upper limit is found: Above a certain temperature, gas-phase reactions become important and their effects cannot be neglected. Here, we apply a microwave field to a catalyst-support ensemble capable of direct microwave heating (MWH). We have taken extra precautions to ensure that (i) the solid phase is free from significant hot spots and (ii) an accurate estimation of both solid and gas temperatures is obtained. MWH allows operating with a catalyst that is significantly hotter than the surrounding gas, achieving a high conversion on the catalyst while reducing undesired homogeneous reactions. We demonstrate the concept with the CO2-mediated oxidative dehydrogenation of isobutane, but it can be applied to any system with significant undesired homogeneous contributions.